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Aims: Non-isotopic histone mRNA in-situ hybridization (HmRNA NISH) allows detection of cells in the S phase of the cell cycle in paraffin-embedded tissue. The aim of this study was to evaluate the technique in measuring the proliferative activity of astrocytic neoplasms, and to compare the results with other proliferation estimates and patient survival. Methods and results: The proliferative activity of 71 routinely fixed and paraffin-embedded astrocytomas was studied by light microscopic HmRNA NISH, proliferating cell nuclear antigen (PCNA), Ki67MIB-1 and mitoses. A significant correlation was found between the labelling indices of histone mRNA (the percentage of histone-positive tumour cells; HmRNA-LI), immunohistochemical proliferation marker labelling indices (PCNA-LI: r = 0.64 and Ki67MIB-1-LI: r = 0.44) and mitotic indices (r = 0.45). The results were reproducible as judged by intra- and interobserver agreement (HmRNA/10 HPF (high power fields): r = 0.91 and r = 0.75, respectively, and HmRNA-LI: r = 0.61 and r = 0.62, respectively). The fraction of the cells in the most active cell cycle phases, as suggested by the HmRNA/Ki67 and mitotic index/Ki67 ratios, increased significantly with malignancy grade. In the univariate analysis the association of HmRNA-LI with survival was highly significant (P

Recent studies suggest that aberrations of c-erbB-2 may be involved in astrocytic brain tumours. We screened immunohistochemically c-erbB2 protein (p185) expression in 94 astrocytic grade 1-4 neoplasms of the brain. The amplification of the c-erbB-2 oncogene was investigated in protein overexpression cases by dual colour fluorescence in situ hybridisation (FISH). p185 overexpression was correlated with p53 and epidermal growth factor receptor (EGFR) expression, as well as with clinicopathological features. Only two anaplastic (grade 3) astrocytomas and one glioblastoma (grade 4) showed overexpression of p185 protein by immunohistochemistry (monoclonal MAb1 antibody TA250), whereas none of the grade 1-2 astrocytomas was positive. Interestingly, the expression of p185 was confined solely to the cytoplasm of neoplastic astrocytic cells and not to the cell membranes as found in malignancies with amplification of the c-erbB-2 oncogene. Two of the three overexpression cases were also positive by EGFR. No amplification of the c-erbB-2 gene was observed by FISH in the three tumours with immunohistochemical p185 overexpression or seven weakly positive/negative tumours. In conclusion, our results suggest that p185 overexpression is infrequent in astrocytomas, that it is of no important diagnostic or prognostic value and that c-erbB-2 oncogene amplification is not seen in the few cases in which there is overexpression. Images Figure 1 Figure 2

In mobile Web usage scenarios, taking advantage of user context in information retrieval (IR) and filtering becomes evident. There are multiple ways to approach this, of which we present some alternatives and discuss their performance independently and in combination. The investigation is restricted to Semantic Web like structured content consisting of statements. The discussed approaches address relative importances of statements constituting the content, dependencies between statements, and close matches. Simulated results of the various approaches are provided. (22 refs.)

The aim of the study was to estimate the significance of oxidative/nitrosative damage and expression of antioxidant enzymes in renal cell carcinomas (RCC). For this we investigated immunohistochemically six antioxidant enzymes (AOEs) including MnSOD, ECSOD, thioredoxin, thioredoxin reductase, and gammaglutamyl cysteine synthetase heavy and light chain in 138 RCCs. As an indicator of oxidative/nitrosative damage, sections were stained with an antibody to nitrotyrosine. The extent of apoptosis was evaluated by TUNEL method and proliferation by immunohistochemistry to Ki67. Variable expression of all AOEs could be seen in RCC with expression of MnSOD being strongest. Nitrotyrosine was significantly associated with high grade tumors. MnSOD was associated with tumors of a lower stage. Cases showing ECSOD reactivity had higher and cases expressing thioredoxin lower apoptotic index than other tumors. No association with patient prognosis was observed. According to the results renal cell carcinomas show oxidative/nitrosative damage which, according to nitrotyrosine staining, was higher in high grade tumors. Of AOEs, MnSOD was more abundantly expressed in low stage tumors suggesting that its antioxidant function could play a main role to prevent development of oxidative damage leading to more aggressive tumors.

BACKGROUND: Temporal arteritis is a primary vascular inflammatory disease. The aetiology of temporal arteritis is unknown, but the influence of environmental factors such as infections has been suggested.MATERIALS AND METHODS: We used broad-range PCR, targeting conserved regions of the gene encoding for ribosomal RNA, to detect bacterial DNA in 27 temporal artery biopsies. Five uninvolved temporal arteries were also included. A lung sample of confirmed bacterial pneumonia served as a positive control. Inflammation was examined by histochemistry and light microscopy.RESULTS: The sensitivity of the broad-range PCR assay was 5.0 fg of DNA. Bacterial DNA sequences were neither detected in 27 temporal arteritis specimens nor in the normal temporal artery samples. However, bacterial DNA was successfully amplified from the lung sample of a subject with pneumonia. In addition, human DNA was amplified by primers for human beta-actin from all clinical specimens, suggesting lack of significant inhibitors of the molecular amplification reaction. Histochemistry showed signs of strong inflammation in the arteritis samples.CONCLUSIONS: The lack of detectable amounts of bacterial DNA suggests that viable bacteria do not have a role in chronic stages of temporal arteritis. However, these findings do not rule out the possibility of bacterial degradation products as stimulants of chronic inflammation, or of viable microbes as triggering factors of acute temporal arteritis.

Deregulation of telomerase, a ribonucleoprotein polymerase that compensates progressive loss of telomeric (TTAGGG)n repeats during DNA replication, has been suggested to facilitate tumorigenesis and cellular immortality by providing unlimited proliferation capacity for cancer cells. We investigated the relationship between tumor proliferation activity and in situ expression of the telomerase RNA component in 46 human grade I to IV astrocytomas. Heterogeneously distributed telomerase RNA expression was detected from all of the tumor samples as well as from normal human brain tissue. However, expression of telomerase RNA was significantly increased in highly malignant tumors (P = 0.024) and in tumors that showed increased proliferation activity determined by MIB-1 immunohistochemistry (P = 0.014). Interestingly, increased telomerase RNA levels were observed in a subgroup of grade II astrocytomas that showed significant increase in proliferation activity (P = 0.047), indicating that the telomerase RNA component is up-regulated already in early states of astrocytoma malignancy. Telomeric repeats amplification assays revealed telomerase activity in 4 of 6 glioblastomas and in 1 rapidly proliferating grade II astrocytoma. These results suggest that increased tumor proliferation activity triggers telomerase activation via mechanisms that involve increased production of the telomerase RNA component.